Pollinator Behaviour on a Food-Deceptive Orchid Calypso bulbosa and Coflowering Species

Table 1

The phenological window of Calypso bulbosa flowering in relation to the flowering of the most important nectar sources, early flowering willows (Salix) and later-flowering bilberry (Vaccinium). Overlap of C. bulbosa flowering with the coflowering species is given in number of days. The last column gives total number of Bombus spp. on Salix spp. and number of individuals carrying pollinia.

Year	First flowering C. bulbosa	Overlap with Salix spp.	Days between Salix and Vaccinium	No overlap with Vaccinium	Overlap with Vaccinium	Bombus spp. on Salix spp. (total/pollinia)
2007	<28 May	>4	2	6	≥11	469/33
2008	2 June	6	5	11	≥14	357/25
2009	24 May	6	7	13	≥8	35/0
2010	21 May	2	8	10	≥15	27/1